CN217590825U - Polarization isolation testing device for satellite communication antenna - Google Patents
Polarization isolation testing device for satellite communication antenna Download PDFInfo
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- CN217590825U CN217590825U CN202221749923.3U CN202221749923U CN217590825U CN 217590825 U CN217590825 U CN 217590825U CN 202221749923 U CN202221749923 U CN 202221749923U CN 217590825 U CN217590825 U CN 217590825U
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Abstract
The utility model relates to a polarization isolation testing arrangement for satellite communication antenna, including the antenna principal plane, the subreflector, the feed, the polarization center pin, the polarization motor, the test revolving stage, test motor and base, the antenna principal plane is fixed in test revolving stage top surface, the polarization center pin rotates to be located on the test revolving stage, the polarization center pin is located the central line of antenna principal plane, the feed cover is established in polarization center pin upper end, the feed top is located to the subreflector, the polarization motor is fixed in on the test revolving stage, the test revolving stage rotates and locates on the base, test motor is fixed in on the base, the polarization motor drives the polarization center pin through polarization drive mechanism and rotates, test motor drives test revolving stage and polarization center pin coaxial rotation through test drive mechanism, the rotation direction of test revolving stage is opposite with the rotation direction of polarization center pin. The utility model discloses can realize testing the polarization isolation that all polarization angles of satellite communication antenna correspond in same longitude and latitude place, the test is more comprehensive and efficiency of software testing is high.
Description
Technical Field
The utility model relates to a satellite communication monitoring technology field, concretely relates to polarization isolation testing arrangement for satellite communication antenna.
Background
In satellite communication systems, both circular polarization and linear polarization are commonly used to achieve a larger communication bandwidth within a limited frequency bandwidth. Currently, a commonly used satellite communication system in a C frequency band and a Ku frequency band generally adopts a linear polarization mode, and the linear polarization mode is divided into a horizontal polarization mode and a vertical polarization mode. Theoretically, two orthogonally polarized waves should be completely isolated, which means that one antenna can be provided with two receiving or transmitting ports, each port being matched to only one polarized wave and being completely orthogonal to the other polarized wave. In a satellite communication system, frequency multiplexing can be performed by using the characteristic of orthogonal polarization, that is, two different polarization modes can be adopted to transmit two sets of different signals in the same frequency band, and the two sets of different signals can not interfere with each other as long as sufficient polarization isolation exists between the two sets of different signals. In engineering, an index for measuring the polarization isolation characteristic performance of satellite antenna equipment is called polarization isolation, the communication effect of the satellite communication antenna is directly influenced by the polarization isolation, and some satellite communication antennas are forbidden to be applied by satellite companies because the polarization isolation is too small to interfere with satellite resources.
In general, the polarization of the satellite downlink signal is not ideally horizontal or vertical to the ground, but varies with the latitude and longitude of the earth in which the satellite communications antenna is located. In order to make the receiving polarization direction of the satellite communication antenna consistent with the polarization direction of the satellite downlink signal, when receiving the satellite downlink signal, it is necessary to incline the OMT (orthogonal mode transducer) waveguide port behind the feed source relative to the ground by an angle, which is called the polarization angle of the satellite communication antenna in the satellite system.
The existing method for testing the polarization isolation of the satellite communication antenna comprises the following steps: the method comprises the steps that a tested satellite communication antenna is aligned to a test satellite, a CW continuous wave signal specified by a satellite company is transmitted at a polarization angle through the tested satellite communication antenna, a satellite master station receives a horizontal polarization signal and a vertical polarization signal at the same time, and the polarization isolation of the satellite communication antenna is obtained by comparing the strength difference of the two polarization signals through a frequency spectrograph.
The existing satellite communication antenna polarization isolation testing method can only test the polarization isolation of the satellite communication antenna at one or two polarization angles, such as the chinese patent with publication number CN114171918A, which discloses a calibration method for the polarization isolation of a satellite mobile communication antenna, although the polarization isolation of the satellite communication antenna can be automatically and accurately calibrated without being limited by third-party equipment facilities such as a satellite master station, in the testing process, the polarization isolation of the satellite communication antenna at two polarization angles can only be tested by controlling a polarization axis to change the polarization angle, and in the using process of the satellite communication antenna, the used polarization angle is constantly changed along with the longitude and latitude information and the satellite orbit information of the satellite communication antenna, so the existing satellite communication antenna polarization isolation testing device and related testing method cannot test the polarization isolation corresponding to all polarization angles used by the satellite communication antenna at one longitude and latitude place, that is not guaranteed that the polarization isolation of the satellite communication antenna after leaving a factory meets the company requirements when being used globally.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art's shortcoming, provide a polarization isolation testing arrangement for satellite communication antenna, can realize testing the polarization isolation that all polarization angles of satellite communication antenna correspond in same longitude and latitude place, the test is more comprehensive and efficiency of software testing is high.
The purpose of the utility model is realized through the following technical scheme:
the utility model provides a polarization isolation testing arrangement for satellite communication antenna, including the antenna principal plane, the subreflector, the feed, the polarization center pin, the polarization motor, the test revolving stage, test motor and base, the antenna principal plane is fixed in test revolving stage top surface, the polarization center pin rotates to be located on the test revolving stage, the polarization center pin is located the central line of antenna principal plane, the feed cover is established in polarization center pin upper end, the feed top is located to the subreflector, the polarization motor is fixed in on the test revolving stage, the test revolving stage rotates and locates on the base, the test motor is fixed in on the base, the polarization motor drives the polarization center pin through polarization drive mechanism and rotates, the test motor drives test revolving stage and polarization center pin coaxial rotation through test drive mechanism, the direction of rotation of test revolving stage is opposite with the rotation direction of polarization center pin.
Furthermore, the lower end of the polarization central shaft is provided with an orthogonal mode converter and an up-conversion power amplifier which are matched with the feed source.
Furtherly, test revolving stage includes roof, bottom plate and bracing piece, and the roof passes through bracing piece and bottom plate fixed connection, and the antenna principal plane is fixed in the top surface of roof, and the polarization center pin passes through rolling bearing and is connected with the roof rotation, and the antenna principal plane is upwards passed to polarization center pin upper end, and the roof is passed downwards to polarization center pin lower extreme, and the polarization motor is fixed in the bottom surface of roof, and the bottom plate rotates to be located on the base.
Furthermore, the polarization transmission mechanism comprises a polarization belt wheel and a transmission belt, the polarization belt wheel is fixed at the lower end of the polarization central shaft, and the polarization motor drives the polarization belt wheel to rotate through the transmission belt.
Furthermore, a rotating seat is fixed at the bottom of the bottom plate and is rotatably connected with the base through a rotating bearing.
Furthermore, the test transmission mechanism comprises a driving gear and a driven gear, the rotating gear is fixed on an output shaft of the test motor, the driven gear is fixed on the rotating seat, and the driving gear and the driven gear are meshed with each other.
The utility model has the advantages of it is following:
1. the utility model discloses an antenna principal plane, the subreflector, the feed, the polarization center pin, the polarization motor, the test revolving stage, the setting of test motor and base, with the antenna principal plane, subreflector and feed installation combination are satellite communication antenna, utilize the polarization motor, test revolving stage and test motor adjust communication antenna's polarization angle, can test the polarization isolation that all polarization angles of satellite communication antenna correspond in same longitude and latitude place, satellite communication equipment's production test coverage has been improved, can avoid the risk of satellite polarization interference, thereby guarantee that satellite communication antenna's polarization isolation can both satisfy the requirement of satellite company.
2. The utility model discloses usable machine controller carries out automated control to polarization motor and test motor in the test process, and then can realize satellite communication antenna polarization angle's automatic adjustment, has improved efficiency of software testing and polarization adjustment precision.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is a schematic view of the installation structure of the satellite communication antenna and the polarization motor in FIG. 1;
FIG. 3 is a schematic view of the mounting structure of the testing turntable and the testing motor in FIG. 1;
fig. 4 is a schematic view of the working flow of the present invention;
in the figure: 1. a satellite communication antenna; 11. a sub-reflecting surface; 12. a feed source; 13. an orthogonal mode converter; 14. An up-conversion power amplifier; 2. an antenna main surface; 3. a polarization central axis; 4. a polarized motor; 5. testing the rotary table; 51. a top plate; 52. a base plate; 53. a support bar; 6. testing the motor; 7. a base; 8. a rotating bearing; 9. a polarizing pulley; 10. a drive belt; 15. a rotating seat; 16. a driving gear; 17. a driven gear.
Detailed Description
The invention will be further described with reference to the accompanying drawings, but the scope of the invention is not limited to the following description.
As shown in fig. 1-3, a polarization isolation testing device for a satellite communication antenna comprises an antenna main surface 2, an auxiliary reflection surface 11, a feed source 12, a polarization central shaft 3, a polarization motor 4, a testing rotary table 5, a testing motor 6 and a base 7. Wherein antenna principal plane 2, subreflector 11 and feed 12 constitute satellite communication antenna 1 jointly, polarization center pin 3 is located the central line of antenna principal plane 2, feed 12 cover is established in polarization center pin 3 upper end, feed 12 top is located to subreflector 11, antenna principal plane 2 and polarization motor 4 pass through bolt fixed mounting on test revolving stage 5, test motor 6 passes through bolt fixed mounting on base 7, polarization motor 4 accessible polarization drive mechanism drives polarization center pin 3 and rotates on test revolving stage 5, test motor 6 then accessible test drive mechanism drives test revolving stage 5 and polarizes center pin 3 coaxial rotation on base 7, and the rotation direction of test revolving stage 5 is opposite with the rotation direction of polarization center pin 3.
An orthogonal mode converter 13 and an up-conversion power amplifier 14 are mounted on the lower end of the polarization center axis 3. The up-conversion power amplifier 14 is used for performing frequency conversion and power amplification on the L-band signal output by the satellite modem, and finally transmitting the signal to the orthogonal analog-to-digital converter 13; the orthogonal mode converter 13 is used as a microwave element for separating or mixing two orthogonal polarized waves, mixes a single polarized wave output by the up-conversion power amplifier 14 and radiates the mixed wave to the feed source 12, and simultaneously separates the two orthogonal polarized waves radiated by the satellite to a frequency spectrograph at a signal receiving end; the feed source 12 is used for radiating the radio frequency power output by the up-conversion power amplifier 13 to the sub-reflecting surface 11 in the form of electromagnetic waves; the sub-reflecting surface 11 is used for regularly reflecting the electromagnetic wave radiation energy radiated by the feed source 12 to the main surface 2 of the antenna; the antenna main surface 2 is a conductive curved surface for intensively reflecting the electromagnetic wave emitted from the sub-reflecting surface 11 in a certain direction according to a certain requirement to enhance the emission effect.
Specifically, as shown in fig. 1 and 2, the test turret 5 includes a top plate 51, a bottom plate 52, and a support rod 53. Wherein the top plate 51 is fixedly connected with the bottom plate 52 through a support rod 53, so that the top plate 51 is supported above the bottom plate 52 by the support rod 53, the bottom plate 52 is rotatably arranged on the base 7, and preferably, the top plate 51 and the bottom plate 52 are horizontal. The antenna main surface 2 is fixed on the top surface of the top plate 51 through bolts, the polarization central shaft 3 is rotatably connected with the top plate 51 through a rotating bearing 8, the upper end of the polarization central shaft 3 penetrates through the antenna main surface 2 upwards, and the lower end penetrates through the top plate 51 downwards; the polarization motor 4 is fixedly arranged on the bottom surface of the top plate 51 through bolts; the feed source 12 is sleeved at the upper end of the polarization central shaft 3, the auxiliary reflecting surface 11 is arranged at the top of the feed source 12, and the orthogonal mode converter 13 and the up-conversion power amplifier 14 are arranged at the lower end of the polarization central shaft 3. The radiation of the antenna main surface 2 and the radiation of the auxiliary reflecting surface 11 are realized through space, so that the radiation of the antenna main surface 2 and the radiation of the auxiliary reflecting surface 11 only need to meet the relative position of a focus when the antenna main surface and the auxiliary reflecting surface are installed, and the feed source 12, the orthogonal mode converter 13 and the up-conversion power amplifier 14 can be directly combined by screws in a seamless and precise mode when the antenna main surface and the auxiliary reflecting surface are installed.
As shown in fig. 2, the polarization transmission mechanism includes a polarization pulley 9 and a transmission belt 10, wherein the polarization pulley 9 is fixed at the lower end of the polarization center shaft 3, the polarization motor 4 drives the polarization pulley 9 to rotate through the transmission belt 10, and further drives the polarization center shaft 3 to rotate with the center line of the antenna main surface 2 as the rotation axis, and the polarization center shaft 3 also drives the satellite communication antenna 1 to integrally rotate when rotating, so as to adjust the polarization angle of the satellite communication antenna 1.
As shown in fig. 3, a rotating seat 15 is fixed at the bottom of the bottom plate 52 through bolts, and the rotating seat 15 is rotatably connected with the base 7 through a rotating bearing 8; the test transmission mechanism comprises a driving gear 16 and a driven gear 17, wherein the rotating gear is fixed on an output shaft of the test motor 6, the driven gear 17 is fixed on the rotating seat 15, and the driving gear 16 and the driven gear 17 are meshed with each other. Preferably, the rotation center line of the rotating base 15 is collinear with the center line of the antenna main surface 2, so that the entire test turret 5 rotates coaxially with the polarization center axis 3 when the test motor 6 rotates the base plate 52 via the driving gear 16 and the driven gear 17.
When the polarization isolation test device for the satellite communication antenna 1 is used for polarization isolation test, the whole test flow is shown in fig. 4, and the whole test flow mainly includes the following steps:
s1, an antenna main surface 2, an auxiliary reflecting surface 11, a feed source 12, a polarization central shaft 3, a polarization motor 4, a test rotary table 5, a test motor 6 and a base 7 are installed, so that the antenna main surface 2, the auxiliary reflecting surface 11 and the feed source 12 form a satellite communication antenna 1, the positions of the satellite communication antenna 1 and the test rotary table 5 are adjusted through the polarization motor 4 and the test motor 6, the satellite communication antenna 1 and the test rotary table 5 are enabled to be aligned to a satellite to be tested at the same time, and then CW continuous waves are transmitted to the satellite to be tested through the satellite communication antenna 1.
Specifically, the base 7 is fixed well, and then the antenna main surface 2, the subreflector 11, the feed source 12, the polarization central shaft 3, the polarization motor 4, the test turntable 5 and the test motor 6 are installed, wherein the polarization motor 4 and the test motor 6 are preferably step motors, and the polarization motor 4 and the test motor 6 are connected to a motor controller after installation, which is a conventional technical means and is not described in detail herein.
And S2, receiving and observing a signal difference value of a horizontal polarization signal and a vertical polarization signal of the satellite communication antenna 1 through a satellite main station, and driving the subreflector 11 and the feed source 12 to continuously rotate along with the polarization central shaft 3 through the polarization motor 4, so that the polarization isolation degree of the satellite communication antenna 1 reaches the maximum value.
Specifically, the satellite master station receives the CW continuous waves in the horizontal polarization and the vertical polarization, accesses the received CW continuous wave signals to the spectrometer, and observes a difference between the CW continuous wave signals in the horizontal polarization and the CW continuous wave signals in the vertical polarization through the spectrometer, that is, polarization isolation of the satellite communication antenna 1.
According to the requirements of Intel Sat organization and domestic satellite company, the polarization isolation of the linearly polarized satellite communication antenna 1 is as low as 30dB, so the maximum value of the polarization isolation of the satellite communication antenna 1 in the step is not less than 30dB.
And S3, driving the satellite communication antenna 1 and the polarization central shaft 3 to rotate at an angle along with the test rotary table 5 through the test motor 6.
Specifically, if the test motor 6 drives the test turntable 5 to rotate clockwise x o And then the satellite communication antenna 1 and the polarization center shaft 3 also rotate clockwise x o At this time, the polarization angle of the satellite communication antenna 1 to the CW continuous wave transmitted from the satellite is shifted by x o (ii) a Correspondingly, if the test motor 6 drives the test rotary table5 counterclockwise rotation-x o And consequently the satellite communication antenna 1 and the polarization central axis 3 are also rotated counterclockwise by-x o When the polarization angle of the satellite communication antenna 1 to the CW continuous wave transmitted from the satellite is also shifted by x o Where "-" simply means the direction of rotation is reversed.
And S4, driving the auxiliary reflecting surface 11 and the feed source 12 to reversely rotate along with the polarization central shaft 3 relative to the test rotary table 5 at the same angle through the polarization motor 4, so that the polarization angle of the CW continuous waves emitted by the satellite to be tested by the satellite communication antenna 1 reaches the optimal polarization angle.
Specifically, taking the example that the rotation angle of the test motor 6 driving the test turntable 5 to rotate in step S3 is 5 °, the polarization angle of the satellite communication antenna 1 to the CW continuous wave transmitted by the satellite deviates by 5 °, and if the test turntable 5 rotates clockwise by 5 °, the polarization center shaft 3 is driven by the polarization motor 4 to rotate counterclockwise by-5 ° in this step, so that the polarization angle of the satellite communication antenna 1 to the CW continuous wave transmitted by the satellite to be tested reaches the optimal polarization angle, i.e., the receiving polarization direction of the satellite communication antenna 1 is consistent with the polarization direction of the satellite downlink signal; similarly, if the test turntable 5 rotates 5 ° counterclockwise, the polarization center axis 3 rotates-5 ° clockwise, where "-" only indicates that the rotation direction is opposite.
And S5, receiving and recording the signal difference value of the horizontal polarization signal and the vertical polarization signal of the satellite communication antenna 1 through the satellite main station.
Specifically, after the operations of S3 and S4, a frequency spectrograph is used to observe the signal difference between the horizontally polarized signal and the vertically polarized signal of the satellite communication antenna 1 received by the satellite main station, so as to obtain the polarization isolation degree of the final test. And repeating the steps S3 and S4 until all polarization angles are subjected to the coverage test, and recording all measured polarization isolation degrees.
Through above-mentioned polarization isolation testing arrangement, can test the polarization isolation that all polarization angles of satellite communication antenna 1 correspond in same longitude and latitude place, and then improved satellite communication equipment's production test coverage, can avoid the risk of satellite polarization interference to guarantee that satellite communication antenna 1's polarization isolation can both satisfy the requirement of satellite company. In the testing process, the polarization motor 4 and the testing motor 6 can be automatically controlled by the motor controller, so that the polarization angle of the satellite communication antenna 1 can be automatically adjusted, and the testing efficiency and the polarization adjusting precision are improved.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A polarization isolation testing device for satellite communication antenna is characterized in that: including antenna principal plane (2), subreflector (11), feed (12), polarization center pin (3), polarization motor (4), test revolving stage (5), test motor (6) and base (7), antenna principal plane (2) are fixed in on test revolving stage (5), polarization center pin (3) are rotated and are located on test revolving stage (5), polarization center pin (3) are located the central line of antenna principal plane (2), feed (12) cover is established in polarization center pin (3) upper end, feed (12) top is located in subreflector (11), polarization motor (4) are fixed in on test revolving stage (5), test revolving stage (5) are rotated and are located on base (7), test motor (6) are fixed in on base (7), polarization motor (4) drive polarization center pin (3) through polarization drive mechanism and rotate, test motor (6) drive test revolving stage (5) and polarization center pin (3) coaxial rotation through test drive mechanism, the rotation direction of test revolving stage (5) is opposite with the rotation direction of polarization center pin (3).
2. The polarization isolation test apparatus for a satellite communication antenna according to claim 1, wherein: the lower end of the polarization central shaft (3) is provided with an orthogonal mode converter (13) and an up-conversion power amplifier (14) which are matched with the feed source (12).
3. The polarization isolation test apparatus for a satellite communication antenna according to claim 1, wherein: test revolving stage (5) are including roof (51), bottom plate (52) and bracing piece (53), roof (51) are through bracing piece (53) and bottom plate (52) fixed connection, the top surface of roof (51) is fixed in antenna principal plane (2), polarization center pin (3) are rotated with roof (51) through rolling bearing (8) and are connected, polarization center pin (3) upper end upwards passes antenna principal plane (2), polarization center pin (3) lower extreme passes roof (51) downwards, polarization motor (4) are fixed in the bottom surface of roof (51), bottom plate (52) are rotated and are located on base (7).
4. The polarization isolation test apparatus for a satellite communication antenna according to claim 1, wherein: the polarization transmission mechanism comprises a polarization belt wheel (9) and a transmission belt (10), the polarization belt wheel (9) is fixed at the lower end of the polarization central shaft (3), and the polarization motor (4) drives the polarization belt wheel (9) to rotate through the transmission belt (10).
5. A polarization isolation test apparatus for a satellite communication antenna according to claim 3, wherein: the bottom of the bottom plate (52) is fixed with a rotating seat (15), and the rotating seat (15) is rotationally connected with the base (7) through a rotating bearing (8).
6. The polarization isolation test device for a satellite communication antenna according to claim 5, wherein: the test transmission mechanism comprises a driving gear (16) and a driven gear (17), the rotating gear is fixed on an output shaft of the test motor (6), the driven gear (17) is fixed on the rotating seat (15), and the driving gear (16) and the driven gear (17) are meshed with each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221749923.3U CN217590825U (en) | 2022-07-06 | 2022-07-06 | Polarization isolation testing device for satellite communication antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221749923.3U CN217590825U (en) | 2022-07-06 | 2022-07-06 | Polarization isolation testing device for satellite communication antenna |
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| Publication Number | Publication Date |
|---|---|
| CN217590825U true CN217590825U (en) | 2022-10-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202221749923.3U Active CN217590825U (en) | 2022-07-06 | 2022-07-06 | Polarization isolation testing device for satellite communication antenna |
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| CN (1) | CN217590825U (en) |
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- 2022-07-06 CN CN202221749923.3U patent/CN217590825U/en active Active
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